1. Technical Field
The present invention relates to surgical instruments and, in various embodiments, to surgical cutting and stapling instruments and staple cartridges therefor that are designed to cut and staple tissue.
2. Background
Surgical staplers have been used to simultaneously make a longitudinal incision in tissue and apply lines of staples on opposing sides of the incision. Such instruments commonly include a pair of cooperating jaw members that, if the instrument is intended for endoscopic or laparoscopic applications, are capable of passing through a cannula passageway. One of the jaw members receives a staple cartridge having at least two laterally spaced rows of staples. The other jaw member defines an anvil that has staple-forming pockets aligned with rows of unformed staples supported in the cartridge.
In use, a clinician is able to close the jaw members of the stapler upon tissue to position the tissue prior to firing. Once the clinician has determined that the jaw members are properly gripping tissue, the clinician can then fire the surgical stapler, thereby severing and stapling the tissue. The simultaneous severing and stapling avoids complications that may arise when performing such actions sequentially with different surgical tools that respectively only sever or staple.
A variety of surgical cutting and stapling instruments are known that may be employed laparoscopically and/or in connection with various “open” surgical procedures. Some surgical stapling and severing instruments are configured to support replaceable cartridges that support the unformed staples therein. Such devices commonly employ a retractable cutting member that remains with the stapling instrument and may be reused with several cartridges. After the staples are fired in one cartridge, the cutting member is retracted and the spent cartridge is removed to enable a new cartridge to be installed if desired. As the cutting member is driven distally through the cartridge, the unformed staples are fired out of their respective pockets in the cartridge into forming contact with the underside of the anvil. Examples of such devices are disclosed in U.S. Pat. No. 7,000,818, entitled “Surgical Stapling Instrument Having Separate Distinct Closing and Firing Systems”, issued Feb. 21, 2006, the disclosure of which is herein incorporated by reference in its entirety. Other surgical cutting and stapling instruments employ what is commonly referred to as a “disposable loading unit” or “DLU”. Such devices support a staple cartridge and a fresh knife in the form of a “unit” that is configured to be operably attached to the surgical stapling instrument. The units are designed to be discarded after the staples have been fired. Examples of such instruments are disclosed in U.S. Pat. No. 5,865,361 entitled “Surgical Stapling Apparatus”, issued Feb. 2, 1999, the entire disclosure of which is herein incorporated by reference.
In some circumstances, the layers of tissue can be relatively thin, can have a high fluid content, and/or can have a non-uniform thickness, which can cause the staples to be improperly formed within the tissue. To ameliorate this problem, a piece of “buttress” material has been utilized to support the tissue as the tissue is being clamped and stapled. Such piece of buttress material is commonly releasably attached to at least one of the first and second jaw members before they are inserted into a surgical site. The piece of buttress material serves to distribute the compressive force applied by the staples over the surface area of the tissue in order to create a more uniform pressure distribution within the tissue. U.S. Patent Publication No. US2009/0206143 A1, entitled “Surgical End Effector Having Buttress Retention Features”, published Aug. 20, 2009 discloses various buttresses and buttress retention arrangements and is herein incorporated by reference in its entirety.
In many surgical procedures and, in particular, in many vascular-related surgical procedures, once the tissue is divided by the cutting and stapling instrument, the two segments of tissue fall away from the end effector that supports the staple cartridge. In some procedures involving, for example, the bowel and/or stomach, may not be problematic. However, other tissue types such as vessels have a tendency to rapidly withdraw towards their origin after being severed. For example, in a procedure such as a lung lobectomy, wherein the vessels are generally located within a relatively confined thoracic cavity, once a vessel has pulled away, it can be very difficult to reacquire should the need arise. For example, if the sealing or ligation is flawed and there is bleeding, it is imperative that the vessel be reacquired as quickly as possible to undertake repair of the leaking vessel.
Accordingly, there is a need for surgical staple cartridge arrangements that address many of the challenges discussed above.
The foregoing discussion is intended only to illustrate some of the shortcomings present in the field of the invention at the time, and should not be taken as a disavowal of claim scope.